If you kill an enemy, you should be able to pick up their weapon and use it for a while. It would be a cool feature and would be really funny to see a medic camping on a hill with a sniper. This could balance the scale for new players a ton since they don't have the best weapons unlocked yet. If they kill a player with a high level gun, they can pick it up and use it to balance the fight a little. It wouldn't effect high level players as much other than give classes access to guns they can't get from leveling up.